At present, such services are accessible from a terminal connected to mobile telecommunications networks such as GPRS (General Packet Radio Service) networks and UMTS (Universal Mobile Telecommunication System) networks.
In these mobile networks, to select a communications network offering services, it is necessary to select a name identifying the communications network. To set up a connection between a terminal and a particular communications network, the identifying name is transmitted via a service support equipment of the mobile network to an equipment managing access to the communications networks. The identifying name specified by the terminal enables the service support equipment of the mobile network to determine the access management equipment associated with the identifying name that offers access to the specified communications network.
In existing GPRS and UMTS networks, the name identifying a communications network is called its access point name (APN), the service support equipment is called the serving GPRS support node (SGSN), and the equipment managing access to the various communications networks is called the gateway GPRS service node (GGSN).
An APN primarily comprises an identifier that corresponds to the selected communications network, an identifier of the operator managing the communications network, and an identifier of the technology of the mobile network, for example the GPRS technology. The format and use of an APN are covered by standards issued by the ETSI (European Telecommunications Standards Institute).
One function of an SGSN is to receive an APN from a terminal and to send it to an APN server to which it is connected in order for the APN to be recognized. The APN server responds to the SGSN by sending a list of the GGSN associated with the specified APN. One function of the SGSN is to set up a connection to a GGSN from the list. The GGSN sets up a connection to a communications network that corresponds to the APN. The SGSN and the GGSN are also covered by ETSI standards.
To access a communications network offering a set of services, the user selects an APN on the terminal in order to set up a connection with the corresponding communications network.
Once an APN has been selected on the terminal, an access protocol is initialized. In a GPRS or UMTS network, this protocol is the packet data protocol (PDP). A procedure is executed to set up a connection from the terminal to the GGSN. To enable the connection to be set up, a link across the mobile network to the selected communications network is created. In a GPRS or UMTS network, that link is called a PDP context. It enables the terminal to access the services of the communications network.
At the end of the set-up procedure, the terminal receives from the communications network to which a connection has been set up an address that identifies the terminal within the communications network and is associated with the PDP context linking the terminal and the communications network.
The ETSI standard provides for a plurality of connections to be set up simultaneously from the same terminal to different communications networks. The document FR 02 07457 describes the use of a dedicated architecture manager in a terminal to manage simultaneous access to a plurality of communications networks.
In that document, on establishing a connection to a communications network, the dedicated architecture manager dialogues with the communications network. In the terminal, the dedicated architecture manager designates an architecture dedicated to the connection to the connected communications network. On setting up each new connection to a new communications network, the dedicated architecture manager designates a different architecture dedicated to the connection to the new communications network. The various dedicated architectures in the same terminal operate simultaneously. Each dedicated architecture is associated with a PDP context and provides access to a different communications network.
The above document mentions that each dedicated architecture comprises a network interface. Each communications network communicates with a dedicated architecture of the terminal via a separate network interface. The address sent by each of the communications networks is received by the dedicated architecture manager and its parameters are set via a network interface. A network interface of any dedicated architecture is unrelated to any other network interface of any other dedicated architecture.
The dedicated architecture manager in a terminal assigns each dedicated architecture to a communications network. The autonomy and independent operation of the dedicated architecture of the terminal guarantee confidentiality and security between communications networks by providing a “seal” between the various services connected to the terminal.
To maintain the independence of the various communications networks effectively, a dedicated architecture has no functions for managing the associated PDP context created via the mobile network to enable access from the terminal to a communications network.
Moreover, because of the autonomy of the various dedicated architectures of a terminal, each dedicated architecture has no view of the operation of the other dedicated architectures of the terminal.
The document WO 02/30056 describes a system for managing quality of service after a mobile terminal has accessed a private network. The mobile terminal accesses various applications via a gateway and via this one private network. The base station associated with the mobile terminal identifies the appropriate quality of service for each of the applications corresponding to the various IP (Internet Protocol) data packets sent over the private network. The above document does not describe selection for the purposes of access in the terminal to a set of communications networks and management thereof.
The document WO 02/01822 describes a method of securing remote access to a private data transmission network in an IP (Internet Protocol) environment using the functions of a remote access server with GPRS functions. Procedures for managing a PDP context are defined in ETSI and 3GPP standards and provide GPRS connectivity (remote access and security) and for use of the radio resources of the GPRS network. The above document does not explain how remote access with a plurality of networks is selected and managed in a terminal.
The document WO 02/09451 concerns a method of connecting a plurality of terminal equipments TE via a mobile terminal MT to a single packet data network PDN. As the mobile terminal MT receives the IP addresses assigned to each terminal equipment TE from only one data network PDN, the addresses are always different from each other. Consequently, the cited document does not encounter the problem addressed by the invention, i.e. that of selecting on a terminal the functioning of a plurality of architectures each dedicated to a different communications network.